this is by far the best source of pree pdfs for most airport. it creates a remote accessed server, where all the data is stored. i'm sure there's a way to monthly have it updated in the app, although i'm no IT so i can't suggest how.
https://www.autorouter.aero/wiki/aip-library/autorouter offers AIP documents for airports, often referred to as “plates”. These are taken daily out of Eurocontrol EAD’s PAMS library which is the official repository for all participating countries.
There are several uses of these documents within the autorouter platform:
When filing a flight plan, you can choose to receive applicable plates (departure, destination, first alternate, second alternate) via email.
You can access plates for specific airports using the Plates Browser.
The plate library can be accessed using the WebDAV protocol which allows third party applications to view, download and conveniently synchronize the documents.
Note: the complete PAMS library is over 7GB in size so please refrain from downloading data you do not need for your operations.
Accessing WebDAV through the browser
A simple browser interface to the webdav repository is provided at
https://www.autorouter.aero/webdav. You can browse through the library and download individual documents. The difference to the plate browser is that’s organized hierarchically and that it’s file system oriented whereas the plates browser performs airport lookup and is documented oriented.
Setting up WebDAV on your device
You can unleash the full power of the WebDAV interface by using client software that can synchronize with WebDAV repositories and thereby make sure you have an up to date subset of the document library on your devices. There are many WebDAV clients to choose from. As long as they adhere to the standard, they should be able to access the autorouter AIP library. We have prepared instructions for a few popular clients.
WebDAV on Android with FolderSync
WebDAV on iOS with GoodReader
WebDAV on OS X
WebDAV on Windows